Chevrolet Repair Questions? Ask a Chevy Mechanic for Answers ASAP
Hello and welcome.
This sounds like you have a wiring problem. The harness behind both headlights, and runs on the front support bar between the teo healamp assemblies is a known place for wiring problems. Inside that harness, between the two assemblies, water gets into the harness and can corrod a slpice, or any wire in the harness. Need to remove both lamps, strip the covering from the harness at each lamp as it goes down into the lamp cavity, and trace the wires to and from both sides. You will need to pull on the wires as you go along removing more of the insulation/tape. You will most likely find a broken wire or splice near the light that is not working.
If fuses are good, check for power at the headlight that does not work with the headlight switch in the on postion at the dark blue wire.
There is a drl resistor on the outboard of the rt.frame rail. Accessed through the wheel well.(see pic) Ohm spec is .3 ohms. also, the bcm controls the drl relay.